jalal jalal shokouhi-md diffusion imaging of cholesteatomas

Jalal jalal shokouhi-MD

DIFFUSION IMAGING OF CHOLESTEATOMAS

cholesteatomas

Epidermoid inclusion cystCystic creatinin-filled massLined by stratified squamous epitheliumCommon in frontal bone and earCause: secondary to trauma and implanted

inner table, outer table

[email protected] www.medimage.ir

Mucoid like content DDx with mucoceleFat content of cholestrol T1-MR signal

T2

Intermediate

Intermediate

high


Acquired cholesteatoma Expansile concentrically enlarging

collection of exfoliated keratin lined by keratinizing stratified squamous epithelium

Not neoplasm May or may not contain cholesterol crystals Congenital (epidermoid) 2% Acquired in middle ear 98%



Frontal chole.

Acquired: Pars flexia (attic) -> prussak`s space -> mastoid Pars tensa

Acquired: Primary acquired (no infection) Secondary acquired (infection)

Etiology: retraction*, papillary proliferation, immigration, metplasia



prussak`s space- pars flexida

Petrosal cholesteatoma -> Apex



Petrosal chole.APEX


Pars tensa

[email protected] www.medimage.irPars tensa


Pars tensa and tegmental erosion


Ossicular erosion


Facial canal erosion


Acquired cholesteatoma


Auto mastoidectomy

[email protected] www.medimage.irAuto mastoidectomy

Imaging:X-ray CT bone destruction, soft tissue

demo. And complications, uncommon granulation tissue

MR spine-echo non-specific signal moderately Hyperintense (better for tegmen tympani and sinus) exclude

facial nerve involvement GD for granulation tissue versus non-enhancing

cholesteatoma



Epidermoid


EAC chol. with no atresia


Cholesteatoma of EAC with atresia

Cholesteatoma of EAC with atresia

CH. In vestibula


Boney sequestra Ossicular


Chole. In EAC


Large Chole. In EAC


Chole. In middle ear and EAC


Osteopetrosis

In location of geniculate ganglion

Diffusion-weighted imagingCholesteatoma is bright means restricted diffusion and

(T2 shine through) Please be aware eddy current artifacts, susceptibility

artifacts, ghosting artifacts, chemical shift and motion artifacts all are prevalent

Higher magnetic fields increase potential of these artifacts in echo-planar DWI

Turbo spin-echo DWI in known to limit, these distortions

Multi shot fast spin-echo periodically rotated overlapping parallel lines with enhanced reconstructions (PROPELLER) DWI= enhanced detection of the lesion (and limiting artifact in high fields)


If there is no middle ear surgery positive predictive value is 93% and negative predictive value is 100%

Sensitivity and specificity 91-100%

DW FAST-SPIN-ECHO Factor 14

Matrix of resolution: 192 x 256

“a” “b” factor 800 second/mm2

1.5 tesla

9 sections in 2.5 mm

3’ 38”

FOV= 230mm

RSNA 2005

DW non-echoplanarDW of middle ear cholesteatoma differ from

abscess and infected cholesteatoma AJNR

DW for post-operative recurrent JU-radiology


T2 left recurrent cholesteatoma-Right granulation tissue

GD T1 enhanced right-non-enhanced left

DW ab factor: 0 - 2.5 mm both DW ab factor: 800-2.5 mm right left

All complications related to bone destruction (mechanical)

C.O.M., vertigo, labyrinthin fistula(more morbidity) in lat. Semicircular canal (18-49)

Facial nerve palsy or paresis (1%)


jalal jalal shokouhi-md diffusion imaging of cholesteatomas

Documents

space pars

content ddx

squamous epitheliumcommon

frontal bone

implanted inner table

inclusion cystcystic

flexia attic prussak

papillary proliferation